AWR1642BOOST: Raw data capture by DCA1000EVM

Hi, there.

I'm using AWR1642 with DCA1000EVM to store the raw data.

I save the raw data according to the guide book and someone's Matlab code on the community.

Below is the code.

clear;close all;clc;

adc_file_name = 'F:\DCA1000\adc_data.bin';

Samples_Per_Chirp = 256; % complex adc samples per chirp
Number_of_channels = 4;
Chirps_Per_Frame = 64;
Number_of_Frames = 10;

total_samples = 2 * Samples_Per_Chirp * Number_of_channels * Chirps_Per_Frame * Number_of_Frames;

% Open the file and read the data.
fileID = fopen(adc_file_name,'r');

% TSW1400 converts ADC data to offset binary. Convert it back to 2's
% complement.
radar_data = fread(fileID,total_samples,'uint16')-2^15;
fclose(fileID);

% radar_data has data in the following format.
% Rx0I0, Rx0Q0, Rx0I1, Rx0Q1, Rx0I2, Rx0Q2, Rx0I3, Rx0Q3, ...
% The following script reshapes it into a 4-dimensional array.

radar_data = reshape(radar_data, 2*Samples_Per_Chirp, Number_of_channels, Chirps_Per_Frame, Number_of_Frames);

% Convert the data to complex
radar_data_real = radar_data(1:2:end, :, :, :);
radar_data_complex = radar_data(2:2:end, :, :, :);
radar_data = radar_data_real;%+ 1i*radar_data_complex;

% Permute the dimensions of the array are so that they are of the format
% [Channels, Samples, Chirps, Frames]

radar_data = permute(radar_data, [2,1,3,4]);

% plot one channel
a = radar_data(1,:);
plot(a);

And I got the graph.

It seems like FM signal?

If I want to plot the time domain received signal, what should I do?

Or I plot the graph totally wrong? Cuz I can not find any part discussing on content of raw data in the user guide.

Thanks a lot.

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